1st and 3rd cyllinders misfire

I need help!!! I have a 2001 pontiac grand am. I have taken my car to two repair shops-1 being the dealer. When starting my car the whole car shakes. Diagnostics show the first and third cylinders are misfiring but both repair shops say they cannot figure out what the problem is because supposedly those two cylinders should not misfire together. I have been without my car for three weeks now and still owe $7'000 on my loan. I would really like to keep my car but it's no good if nobody knows what is wrong. Can anyone help?

Misfires are caused by one of two things. Spark or fuel. In your case you may need to replace either the injectors or the coils. If this is a 4 cylinder then I would start with the plugs followed by the plug connectors and then the coils. Change the ignition module as a last resort.

Since you don't give much detail about your car then I am assuming that it is a 4. If it is a 6 cyl. then you should change plugs and wires first. If the dealer says they look find have then changed anyway especially if they didn't test them. They are cheap and will often solve many problems. Then change the coils if that doesn't help. If you are still getting misfires then I would change the injectors but if you have less than 100K miles and have been using good quality gasoline then the injectors should not be a problem. Dealers are notorious for taking your money but never solving too many problems especially if the computer says there is nothing wrong.

will bet its a coil... .. but also a chance your module is shot... get it tested .. from what i know autozone can do that for ya